coderef

File system accessLimited availability

The showOpenFilePicker(), showDirectoryPicker(), and showSaveFilePicker() methods request access to files and directories on the user's device and returns a handle for reading and writing to them.

Not yet supported in all major browsers — check the table and provide a fallback.

Browser support

DesktopChrome
1–85Not supported
86+Supportedsince Oct 20, 2020
Current: 155
Edge
12–85Not supported
86+Supportedsince Oct 9, 2020
Current: 154
Firefox
✕Not supportedup to 157
Current: 157
Safari
✕Not supportedup to 27
Current: 27
MobileChrome Android
18–131Not supported
132+Supportedsince Jan 14, 2025
Current: 155
Firefox Android
✕Not supportedup to 157
Current: 157
Safari iOS
✕Not supportedup to 27
Current: 27

How to use

Not supported in Firefox, Safari, Firefox Android, Safari iOS. Use feature detection below and provide a fallback (or a polyfill) for those browsers.

Example

Full syntax and examples are on MDN: createWritable.

Feature detection

JS · check before using
if ("FileSystemWritableFileStream" in globalThis) {
  // FileSystemWritableFileStream is available
} else {
  // load a polyfill or use a fallback
}

Sub-features

Support for each part of the feature (11). The overall table above shows when the whole feature works.

Sub-featureChromeEdgeFirefoxSafariChrome AndroidFirefox AndroidSafari iOS
FileSystemDirectoryHandle.@@asyncIterator868611116.410911116.4
FileSystemFileHandle.createWritable86861112610911126
FileSystemHandle.queryPermission8686✕✕109✕✕
FileSystemHandle.requestPermission8686✕✕109✕✕
FileSystemWritableFileStream86861112610911126
FileSystemWritableFileStream.seek86861112610911126
FileSystemWritableFileStream.truncate86861112610911126
FileSystemWritableFileStream.write86861112610911126
Window.showDirectoryPicker8686✕✕132✕✕
Window.showOpenFilePicker8686✕✕132✕✕
Window.showSaveFilePicker8686✕✕132✕✕